RFR: 8356407: Part of class verification is skipped in AOT training run [v2]

[Ioi Lam]

> Please see [JDK-8356407](https://bugs.openjdk.org/browse/JDK-8356407) for a detailed description of the problem.
> 
> This fix strictly tightens the handling of class verification during CDS dump -- now the `VerificationType::is_reference_assignable_from()` checks are skipped only when dumping the "classic static archive".
> 
> In the AOT training run, CDS is configured to dump a "preimage static archive". I.e.,
> 
> - `CDSConfig::is_dumping_classic_static_archive()` == false
> - `CDSConfig::is_dumping_preimage_static_archive()` == true
> 
> Therefore, the skipping no longer happens.
> 
> I added a test case and improve the comments in the C++ code.
> 
> (This bug is caused by [JDK-8348426](https://bugs.openjdk.org/browse/JDK-8348426), which is new in JDK 25. So it does not affect JDK 24 or earlier releases).

Ioi Lam has updated the pull request incrementally with one additional commit since the last revision:

  @coleenp comments

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/25104/files
  - new: https://git.openjdk.org/jdk/pull/25104/files/bdfed0d5..5c795980

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25104&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25104&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/25104.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25104/head:pull/25104

PR: https://git.openjdk.org/jdk/pull/25104